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Lethal and Sublethal Effects of Hemoxidants, Particularly Nitrite, on Selected Aquatic AnimalsHuey, David W. (David Worley) 05 1900 (has links)
A research program was developed to investigate basic and applied aspects of toxicity, both lethal and sublethal, of hemoxidants, particularly nitrite, on fish, non-fish aquatic vertebrates, and crayfish. The major objectives of this research were to determine A) acute and sublethal toxicity of nitrite to selected aquatic organisms: 1. aquatic salamander larvae, Ambystoma texanum, 2. swamp crayfish, Procambarus simulans, 3. bluegill, Lepomis macrochirus, 4. bullfrog, tadpoles, Rana catesbiana, 5. channel catfish, Ictalurus punctatus, B) the influence of environmental chloride on acute and sublethal exposures to hemoxidants: 1. on acute nitrite toxicity to salamander larvae, crayfish, and bluegill, 2. on nitrite-induced methemoglobinemia in bullfrog tadpoles, Rana catesbian, C) the effect of environmental hydrogen ion concentrations (pH) on acute nitrite toxicity 1. to the crayfish, Procambarus simulans, 2. to the bluegill, Lepomis macrochirus, D) the effect of temperature in sublethal exposures to nitrite 1. methemoglobin formation in channel catfish exposed at different acclimation temperatures, 2. recovery from methemoglobinemia at different acclimation temperatures, E) the effect of the fish anesthetic TMS-222 on nitrite-induced methemoglobinemia in channel catfish 1. supression of nitrite-induced methemoglobinemia, 2. dose-response curve for TMS-222 induced methemoglobinemia, and F) if a methemoglobin reductase system is present in channel catfish.
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An assessment of the impact of the black village communities, their associated land-use and related practices on water quality of the Kat River in the Eastern Cape, South AfricaSoviti, Malixole Knottien 16 May 2013 (has links)
Amongst others, the South African National Water Act No. 36 of 1998 acknowledges that access to sufficient safe and clean water is a basic right to all South Africans. However, it is well known that millions of inhabitants of rural communities in South Africa are still deprived of this right. Many rural communities in South Africa are thus consuming unsafe, untreated water everyday, thereby exposing themselves to waterborne diseases. The main reason of concern however is the fact that, nevertheless, little is known about rural water quality in South Africa as most water quality work is being undertaken in urban areas. The study's aim is twofold: first, the study examines the impact of Black rural communities' land-use and related activities on water quality and second is specifically, to study the washing practices of the rural communities in the upper Kat River area. To understand the potential impacts of the upper Kat River Black village communities and their associated land-use practices on the quality of upper Kat River catchment, prominent land-use and related activities in the area were investigated. Study area maps were studied and field surveys undertaken to observe major land-use and related activities in the area. The results of the study show that most used land in the area is being utilised for agricultural activities. Settlements and commercial forestry also occupy considerable areas of land. The literature survey suggests that such land-use could have a considerable degrading impact on the quality of both surface and groundwater. The study also investigated the impact of the in-stream use of detergents on water quality in the upper Kat River valley, Eastern Cape - South Africa. In-stream washing practices of certain communities in the upper Kat River valley were investigated and the impact of detergents on water quality was assessed. Recovery of the flow from the input of detergents was also measured. During the study, it has been ascertained that doing laundry by the stream is the common practice in the study area. Water quality analysis results show a remarkable increase on the levels of chloride, turbidity, and electrical conductivity in water as a consequence of direct input of detergents practice into the river during the washing. The recovery of the water quality at a distance of 1km from site of input was almost complete. Water quality monitoring programme was undertaken to establish a link between land-use and the quality of water. In a water quality study routine carried out for a period of 40 weeks on a twice monthly frequency, the state of the flows of the river was determined; water samples were collected at pre-determined points; and the in situ analysis of selected water quality variables (with the exception of the faecal coliforms whose analysis was carried out in the biotechnology laboratory) was carried out. Results of the study showed that the concentration of the studied water quality variables in the area varied widely with time. A clear distinction in concentration of variables such as electrical conductivity, turbidity, pH, total hardness, chloride, and nitrate was evident at the high compared to the low flow period of the study. The concentration of the studied water quality variables in the upper Kat River catchment area also seemed to vary over space. The concentration of variables such as electrical conductivity, pH, total hardness, chloride, nitrate, potassium, number of faecal coliform bacteria per 100ml was observed to be higher in most of the tributary streams than the main river. Turbidity however was orders of magnitude higher in the Kat River than the rest of the tributaries. Most importantly however, results of the study showed that there is a strong link between the quality of water and land-use and related activities in the area. The spatial results of the study showed a strong connection between some land-use and the concentrations of water quality variables. For example, areas of intense grazing were noted with high concentrations of nutrients like nitrate and a higher number of faecal coliform bacteria per 100 ml of water. It was established during the study that land-use and related activities in the upper Kat River valley are negatively impacting on the quality of water thereby rendering it less fit for use for domestic purposes. The continued use of the polluted water by the communities is thus accompanied by a danger of the outbreak of waterborne diseases like cholera. When the concerned communities met in a workshop to discuss the issue of quality of their water, they committed themselves to: • shunning water polluting activities, • at least boiling their drinking water before consuming it. The communities also requested a meeting with the Department of Water and Forestry officials to request a treated, piped supply of water. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
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A poluição das águas do Rio Bauru vista sob a perspectiva da pedagogia histórico-crítica /Genovez, Cinthia Letícia de Carvalho Roversi. January 2006 (has links)
Orientador: José Misael Ferreira do Vale / Banca: Neusa Maria Marques de Sousa / Banca: Jandira Líria Biscalquini Talamoni / Resumo: A crise ambiental que o planeta enfrenta tem sido motivo de grande preocupação por parte de muitos países. No modelo civilizatório atual predomina o desperdício e o consumo desenfreado. Dessa forma, a Educação Ambiental, na perspectiva sócio-ambiental passa a ser um instrumento de conscientização no propósito de formar cidadãos comprometidos com a mudança de valores, atitudes e comportamentos. Um dos muitos problemas ambientais é a questão da poluição das águas. Compreender a poluição das águas é de fundamental importância, já que a preservação de sua qualidade consiste em preservar a própria vida. Portanto, a partir destes questionamentos buscou-se, nesta pesquisa, trabalhar uma nova proposta para o trabalho pedagógico: a Pedagogia Histórico-Crítica (PHC), a fim de responder a questões do tipo: É possível trabalhar em sala de aula o tema da poluição das águas, tendo como referência a Pedagogia Histórico-Crítica como metodologia de ensino? Quais os resultados de sua aplicação? Para responder a essas e outras questões constituídas no caminho da investigação, trabalhou-se, durante um semestre letivo, nas aulas da disciplina Biologia, em uma turma da terceira série de Ensino Médio de uma Escola Pública Estadual do Município de Bauru - SP. Os instrumentos utilizados com o propósito de alcançar os objetivos da pesquisa foram a Observação, o Diário de Aprendizagem, Relatórios das Aulas de Campo e Comentários de Textos. Para a análise dos dados foram utilizados os cinco momentos previstos na própria PHC, teoria pedagógica de Dermeval Saviani, divulgada no Brasil nos anos iniciais da década de 1980 e "traduzida" didaticamente por João Luiz Gasparin, em 2002. A análise dos dados demonstra que a PHC foi um referencial metodológico que conseguiu articular de forma satisfatória o tema abordado / Abstract: The ambient crisis that the planet faces has been reason of great concern for many countries. In the current civilization model it predominates wastefulness and the wild consumption. Of this form, the Environmental Education, in the partnerambient perspective starts to be an instrument of awareness in the intention to form citizens compromised to the change of values, attitudes and behaviors. One of the many ambient problems is the question of the water pollution. To understand the pollution of waters is of basic importance, since the preservation of its quality consists of preserving the proper life. Therefore, to leave of these questionings one searched, in this research, to work new a proposal for the pedagogical work: the Description-Critical Pedagogy (PHC); in order to answer the questions: Is possible to work in classroom the subject of the pollution of waters having as reference the Description-Critical Pedagogy as education methodology? Which the results of its application? To answer to these and other questions consisting in the way of the inquiry, one worked, during a period of learning semester, in the lessons of disciplines Biology, in a group of the Third Series of Average Education of a State Public School of the City of Bauru - SP. The instruments used in order to reach the objectives of the research had been the Comment, the Daily one of Learning, Reports of the Lessons of Field and Commentaries of Texts. For the analysis of the data the five moments foreseen in the proper PHC had been used, Dermeval Saviani's pedagogical theory, divulged in Brazil in the initial years of the decade of 1980 and "translated" for João Luiz Gasparin in 2002. The analysis of the data demonstrates that the PHC was a method reference that obtained to articulate of satisfactory form the boarded subject / Mestre
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Polyamic acid-graphene oxide nanocomposite for electrochemical screening of antibiotic residues in waterHamnca, Siyabulela January 2015 (has links)
>Magister Scientiae - MSc / Pollution of water sources, aquifers and wetland systems caused by industry, agriculture, and municipally treated wastewater is a worldwide problem that contributes to the scarcity of clean and potable water. Rivers, channels, lakes, oceans, and ground water are often contaminated by a variety of organic substances that can affect aquatic life and threaten human health. Organic compounds such as antibiotics that are not effectively removed by modern day water treatment technology are a growing threat to water quality and health. The emergence of antibiotics in the environment particularly aquatics have become a matter of concern as they may result in induction and spread of bacterial resistance which may be harmful to humans or animals. After administration, antibiotics for human use or their metabolites are excreted into the effluent and reach the sewage treatment plant (STP). Not all Antibiotics in sewage treatment plants are eliminated. Consequently they can pass through the sewage system and may end up in environmental and even potable water systems. Antibiotic residues have been reportedly found in places such as hospital wastewaters, wastewater treatment plants and surface waters all over the world with concentrations ranging from approximately 60-120000 ng/, 2-580 ng/L and 5-1300 ng/L respectively. The current methods that are used to detect antibiotics can be quite expensive and time consuming due to sample preparation (necessary for detection of very low concentrations of antibiotics in water) and technology used in the instruments. Electrochemical sensors and biosensors are simple systems, with high selectivity and sensitivity for individual measurements and cost effectiveness. The development of composites based on conductive phases dispersed in polymeric matrices has led to important advances in analytical electrochemistry. Polyamic acid and graphene oxide are both materials with well-defined electrochemistry and are easily processable in the design of various sensor formats. In this study we present a novel polyamic acid - graphene oxide (PAA/GO) electrode which was prepared for electrochemical screening of antibiotic residues in aqueous systems. Polyamic acid (PAA) and graphene oxide (GO) were successfully synthesized independently and characterized using SEM which was used to study the morphology of the PAA, FTIR spectroscopy to confirm chemical structures and functional groups as well as CV and SWV which were used to identify the unique electrochemical behavior of PAA and GO respectively. Polyamic acid-graphene oxide nanocomposite was prepared and characterized by CV, SWV, FTIR and SEM. The novel electrode (PAA/GO/SPCE) was prepared by electrochemically depositing PAA/GO (0.03 mg/mL) onto SPCE electrodes using 5 cycles between −1000 mV and 1000 mV at 50 mVs. The analytical performance of the electrochemical sensor towards detection of neomyxin and norlfoxacin was compared to standard Uv-vis spectroscopy method. The Uv-vis spectroscopy showed LOD of 1.61x10-5 M and 1.41x10-5 M for norfloxacin and neomycin respectively. The PAA/GO electrochemical sensor had a LOD of 3.37x10-7 M for norfloxacin and 1.066x10-6 M for neomycin. Sensitivity of the UV/vis method was comparable to electrochemical sensor sensitivity for neomycin and norfloxacin.
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Hodnocení vlivu krajinné struktury na znečištění povrchových vod v CHKO Křivoklátsko s využitím ArcSWAT / Impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area using ArcSWATHanzlová, Markéta January 2018 (has links)
The topic of thesis deals with a hydrological model SWAT used for impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area. For this purpose using ArcSWAT in the ArcGIS environment there were built hydrological models of three watersheds of various landscape structure located in the area of interest. The measured data of nitrate were used for these models. Concentration of nitrates in the surface waters were simulated by using these models in the period from 2003 until mid-2014. The statistical evaluation of the models including actual landscape structure did not show satisfactory match of the simulated values with the measured values. Due to the uncertainties of the model, including insufficient quantity of measured nitrates, it was not possible to expect exact results. After validation of basic models, it was important to create new models that would include various scenarios of landscape structure organization. New versions represented changes in the use of land classified as arable land in pasture or mixed forests, in the area around the stream to 250 m and 500 m. Modelling of the impact of individual scenarios on the structure of the landscape structure on nitrate concentrations there was displayed a positive effect of grassing and afforestation of...
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Determination of Polycyclic Aromatic Hydrocarbons (PAHS) resulting from wood storage and wood treatment facilities for electricity transmission in SwazilandVan Zuydam, Constance Sthembile 30 June 2007 (has links)
A study was conducted in two sites: one at an electricity storage facility belonging to
the Swaziland Electricity Board (SEB) and the other at a facility that belongs to its
treated pole supplier, the Thonkwane wood creosote treatment plant. The drainage
system of these sites leads to surface waters in rivers. This is a cause of concern
since creosote contains polycyclic aromatic hydrocarbons (PAHs), which are listed
as priority pollutants by the US Environmental Protection Agency. They have toxic,
mutagenic and carcinogenic effects and as a result they pose a threat to human life
and the environment. No previous studies have been done on PAHs in Swaziland.
The main objective of this study was to determine the impact of the SEB storage
facility and the creosote treatment plant by investigating the extent of PAHs in
surrounding environments (soil, sediments and surface waters).
Preliminary studies were undertaken on the storage facility and the creosote
treatment plant. No PAHs were detected from the pole storage facility; therefore the
creosote wood treatment facility was selected as the ideal site at which to conduct
the research. Soil samples were collected from depths 15 cm and 60 cm at points
around the creosote plant, including effluent discharge points. The samples were
extracted by solid-phase micro extraction (SPME) and analysed by GC/MS. The
GC/MS, incorporating a solid phase micro extraction step, provided detection limits
ranging from 0.12 μg/g to 20.08 μg/g. The pollution patterns in the study site were
assessed using cluster analysis and principal component analysis.
Most of the 16 US EPA-listed priority pollutants were detected from the creosote
wood treatment facility. PAHs such as anthracene, fluorene, naphthalene and
fluoranthene were dominant in all the sampling sites. The compounds occurred in
very high concentrations (0.64, 0.46, 0.27 and 0.26 mg/kg respectively). These
compounds are found in pure creosote as determined in the sample taken from the
Thonkwane creosote tank site. The highest concentration of PAHs was observed in
the soil samples taken next to the road site.
The concentrations of the identified PAHs were above the acceptable minimal level
allowed in soil by the US EPA and Swaziland Environment Authority (SEA). The
levels of the PAHs are also above the recommended US EPA limit in soil, which is
0.1 mg/kg. The results indicated that significant soil pollution was taking place in
some of the sampling sites.
The top layer (0, 15 cm) contained many PAHs at high levels whilst the 60 cm layer
had a lower number of PAHs which were also in low concentrations. This provided
an indication that there is no downward movement of PAHs from the surface layer to
underground layers. The potential exists for contamination of surface waters when
there is runoff from the project area. This is a cause of concern, since both the
creosote treatment plant and areas outside the facility are contaminated. Therefore,
the site has to be cleaned up, preferably by using a phytoremediation technique. / Environmental Sciences / M. Sc. (Environmental Science)
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Importance of Concentrated Flow Paths in Agricultural Watersheds of Southern IllinoisShrestha, Prabisha 01 May 2017 (has links)
Field scale research shows concentrated flow paths (CFPs) are prevalent in agricultural watersheds. They are an important source of soil erosion in cropland and significantly contribute to the transport and delivery of agricultural pollutants such as sediment and nutrients to nearby water resources. High resolution LiDAR data have enabled the investigation of the prevalence of concentrated flow at a large geographic extent. This study focused on identifying CFPs in 389 agricultural fields in Jackson County in southern Illinois and estimating the contribution of the CFPs to drainage of the fields. Addressing the lack of literature on factors influencing CFP characteristics, this study also investigates various topographical and soil factors that influence CFP development. LiDAR derived DEMs with a cell resolution of 3 meters were used to identify areas of flow concentration and delineate a drainage basin of each CFP using the Hydrology tools in the Spatial Analyst toolbox in ArcMap 10.3.1. Information on the topographical and soil characteristics were obtained from the DEMs and SSURGO database using the Soil Data Viewer 6.2 extension for ArcMap. Multiple regression analysis in SAS v. 9.4 was used to identify factors influencing CFP characteristics, while CART analysis in R v. 3.3.1 was conducted to detect linear dependencies among predictor variables. An average of 5 CFPs per agricultural field were observed in the study area with a minimum of 0 and maximum of 17 CFPs, but only two fields had no CFPs indicating a high prevalence of CFPs throughout the study area. The mean percent of field area drained by CFPs was estimated to be 81 percent with minimum of 36 percent and ii maximum of 100 percent. The majority of the fields, 85 percent, had more than 70 percent of their area drained by CFPs. Statistically significant regression equations were found for all CFP characteristics with slope, LS factor, K factor and organic matter as the factors influencing CFP characteristics. However, the factors only explained 2 to 22 percent of variation observed. Both multiple regression and CART analysis indicated slope as the most important influencing factor. Variation in CFP characteristics followed regional trends with higher values in the floodplain region and lower values in the rough hills region suggesting residual variation could be explained by other environmental factors along with topographical and climatological factors which were not included in the study. Results from this study highlight the prevalence of CFPs at a regional scale and their substantial contribution to field drainage identifying a need for research in quantifying the impacts of CFP on soil loss and water quality. This study also reports a need of future research to identify important factors controlling CFP formation and development that could help build empirical and physical models to accurately predict CFP locations and morphology. Such information could be useful in designing and targeting conservation practices that protect both soil health and water quality.
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Responses of intertidal macroalgae and associated fauna to interactive processes acting over multiple spatial scales / For AppMostert, Bruce Petrus 01 December 2010 (has links)
The decrease of biological diversity from low latitudes near the equator towards high latitudes is one of the most fundamental patterns noted in ecology. These trends have been the subject of numerous terrestrial and marine studies and have caused the proposal of several explanatory hypotheses. No single hypothesis has adequately accounted for these observed trends. Furthermore, large-scale patterns are frequently modified by processes acting at meso- to small-scales. It is imperative to understand the interaction of these processes to elucidate the mechanisms controlling the structure of intertidal assemblages. The main aim of this thesis was to test the influence of multiple processes at a range of spatial scales on biogenic engineers. Biogenic engineers, such as macroalgae, have been reported to be strongly influenced by processes such as grazing, biogeography and upwelling and subsequent effects are expected to be linked to their associated assemblages. I used infaunal assemblages associated with macroalgae as a model system to understand the interactive effects of meso-scale upwelling in conjunction with large-scale factors (regional and biogeographic). Three species of macroalgae, Hypnea spicifera, Champia lumbricalis and Bifurcaria brassicaeformis, inhabiting different but overlapping home ranges were used in this study. Smaller scale, physical attributes and the associated fauna of these algal species were compared. The effects of meso- to large-scale physical gradients on marine organisms have been investigated in many instances and resultant gradients in physical variables observed. This study was undertaken to investigate morphological trends exhibited by Hypnea spicifera and Champia lumbricalis to compare possible similarities between coastlines and to determine if inferred meso- to large-scale processes influence physical trends in a similar manner despite the coastlines being affected by different hydrodynamic processes. The macroalgae were located in two distinctly different upwelling regimes, Hypnea spicifera on the east and south coasts and Champia lumbricalis on the west coast. Upwelling (delivery of nutrients and primary production) was not found to be an important factor in determining the physical characteristics of macroalgae but there were clear patterns linked to latitude. Mean percentage cover of Hypnea spicifera was positively correlated with distance along the east and south coasts. Mean mass and mean surface area of H. spicifera were, however, negatively correlated with distance from Port St Johns. Mean frond length showed a negative trend but this relationship was not statistically significant. On the west coast, there was a significant increase in mean frond length from north to south for Champia lumbricalis. Mean surface area and mean mass of C. lumbricalis exhibited non-significant negative trends from north to south while there was a non-significant positive trend for mean percentage cover. Following the “Productivity Hypothesis”, these patterns from north to south along the coastlines of South Africa could have important implications for biodiversity associated with these algae. Many previous studies have focussed on the effects of upwelling on species (i.e. effects of nutrients and temperature) but have failed to separate this effect from large scale effects such as biogeography and latitudinal gradients. I tested the influence meso-scale upwelling, large-scale biogeographic processes and latitudinal gradients with two different species of macroalgae one on the east and south coasts of South Africa and the other on the west coast. Hypnea spicifera inhabits the east and south coasts of South Africa spanning two biogeographic provinces and is generally affected by relatively weak upwelling, whereas Champia lumbricalis inhabits the west coast spanning one biogeographic province which is subjected to intense persistent upwelling year round. Within the east and west coast biogeographic provinces there are, however, regions with both upwelling and non-upwelling. On the east and south coasts, entire assemblages differed significantly among the three Regions (St Lucia, Port Alfred and Knysna, while assemblages between upwelling/non-upwelling areas were not different. Assemblages on the different shores differed significantly from each other. There were no significant effects of region or upwelling for the number of individuals of Crustacea or Polychaeta, while Mollusca showed a significant effect of region. The number of individuals of other taxa showed a significant interaction of region and upwelling. Region had a significant effect on number of species of molluscs and other taxa, while there was no effect for either region or upwelling for the Crustacea or Polychaeta. In general different factors were shown to be important (region and shore) while upwelling was rarely important. On the west coast assemblages associated with C. lumbricalis were not influenced by region or upwelling but there were significant differences between shores. Region, upwelling ad shore did not affect number of individuals. There was a significant interaction of region and upwelling for the number of species of crustaceans, while numbers of species of Mollusca, Polychaeta and other taxa showed no effects. In general, regional factors strongly influenced most organisms, while upwelling played a minor role. Hypotheses about differences between upwelling and non-upwelling regions in terms of species abundances and composition due to the input of cold nutrient rich water were not supported. A link between the effects of larger-scale biogeographic factors and their influence on habitat forming taxa and the resultant effects on associated infauna would be a likely explanation for the patterns observed in this study. Diversity of assemblages is known to be influenced by the structural complexity of a habitat, increasing complexity increases the amount of available niches therefore potentially increasing the number of species found within that habitat. Three species of macroalgae, Hypnea spicifera, Champia lumbricalis and Bifurcaria brassicaeformis were selected on the basis of being structurally similar and having their distributional ranges overlap in order to elucidate the effects of structure and macroalgal species on associated assemblages. Hypnea spicifera is different in terms of surface area and biomass from Champia lumbricalis and Bifurcaria brassicaeformis. Assemblages of species found on the three rhodophytes showed both shore and the species of alga had significant effects on composition. Only numbers of individuals of molluscs were affected by the species of alga. Crustacea and Polychaeta showed an interaction of the species of alga with shore. In the case of this study, it is likely that the three species of macroalgae mitigate biological stressors such as predation and physical stressors such as wave exposure and desiccation. In general, meso-scale upwelling is suggested to be marginalised when considering the structuring of assemblages associated with macroalgae, while large scale biogeography has more of an influence. Within shores, assemblages were also strongly influenced by smaller-scale factors such as differences in the structure and species of alga. This study indicates the importance of investigating patterns across a range of spatial scales to gain a comprehensive understanding of factors influencing intertidal organisms.
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Avaliação do risco ecológico de metais em sedimentos da Baía de Guanabara (RJ), através de um método escalonado baseado em múltiplas linhas de evidências /Campos, Bruno Galvão de. January 2017 (has links)
Orientador: Denis Moledo de Souza Abessa / Resumo: A Baía de Guanabara concentra aproximadamente 70% das indústrias do Estado do Rio de Janeiro. Os resíduos produzidos por essas fontes, somados à carga de esgoto doméstico, transformaram a região em umas das áreas mais poluídas da costa Brasileira. O presente estudo realizou a avaliação do risco ecológico dos metais em sedimentos da Baía de Guanabara, por meio de um método escalonado utilizando múltiplas linhas de evidência: caracterização do sedimento quanto à sedimentologia e concentração de metais, comparação das concentrações ambientais com guias de qualidade de sedimento, ensaios de toxicidade crônica utilizando os organismos Anomalocardia brasiliana e Nitocra sp., ensaios de toxicidade aguda utilizando os organismos Tiburonella viscana, Kalliapseudes schubartii, e Anomalocardia brasiliana. Para comprovar existência de relação causa e efeito entre os metais e a toxicidade, foram empregadas a técnica do TIE, análises multivariadas (PCA) e matrizes qualitativas. Os sedimentos mostraram níveis altos a moderados de metais (Zn, Pb, Cu, Cr) associados com a toxicidade. O TIE revelou que, além dos metais, amônia e compostos orgânicos são contaminantes presentes na região que tem a capacidade de causar toxicidade. Desse modo constatou-se que os metais constituem uma importante classe de contaminantes para a Baía de Guanabara, os quais, além de estarem presentes em altas concentrações, interagem com outros contaminantes e são também (co)responsáveis por efeitos biológicos negativos / Abstract: The Guanabara Bay (GB) comprises approximately 70% of the industries of Rio de Janeiro State. The wastes produced by these sources, combined with the domestic sewage loads, have transformed the region into one of the most polluted areas of the Brazilian coast. The present study evaluated the ecological risk of metals in sediments from the GB by the use of a tiered approach. The chosen method combines the following lines of evidence: geochemistry, comparison of environmental concentrations of metals with sediment quality guidelines, chronic sediment toxicity tests with Anomalocardia brasiliana and Nitocra sp.; and acute sediment toxicity tests with Tiburonella viscana, Kalliapseudes schubartii, and Anomalocardia brasiliana. To verify the existence of cause and effect relationships between metals and toxicity, the Toxicity Identification Evaluation (TIE) technique, multivariate analysis (PCA) and qualitative matrices were used. Sediments showed high to moderate levels of metals (Zn, Pb, Cu, Cr) associated with toxicity. In addition, the TIE has revealed that metals, ammonia and organic compounds contribute to cause sediment toxicity. We concluded that metals are an important class of contaminants for the GB, together with other chemicals, as they are present in high concentrations, interact with other substances and are (co)responsible for the negative biological effects / Mestre
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A poluição das águas do Rio Bauru vista sob a perspectiva da pedagogia histórico-críticaGenovez, Cinthia Letícia de Carvalho Roversi [UNESP] 27 March 2006 (has links) (PDF)
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genovez_clcr_me_bauru.pdf: 1838248 bytes, checksum: 8143db954630c4eae3b67bcf4c8f6983 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A crise ambiental que o planeta enfrenta tem sido motivo de grande preocupação por parte de muitos países. No modelo civilizatório atual predomina o desperdício e o consumo desenfreado. Dessa forma, a Educação Ambiental, na perspectiva sócio-ambiental passa a ser um instrumento de conscientização no propósito de formar cidadãos comprometidos com a mudança de valores, atitudes e comportamentos. Um dos muitos problemas ambientais é a questão da poluição das águas. Compreender a poluição das águas é de fundamental importância, já que a preservação de sua qualidade consiste em preservar a própria vida. Portanto, a partir destes questionamentos buscou-se, nesta pesquisa, trabalhar uma nova proposta para o trabalho pedagógico: a Pedagogia Histórico-Crítica (PHC), a fim de responder a questões do tipo: É possível trabalhar em sala de aula o tema da poluição das águas, tendo como referência a Pedagogia Histórico-Crítica como metodologia de ensino? Quais os resultados de sua aplicação? Para responder a essas e outras questões constituídas no caminho da investigação, trabalhou-se, durante um semestre letivo, nas aulas da disciplina Biologia, em uma turma da terceira série de Ensino Médio de uma Escola Pública Estadual do Município de Bauru – SP. Os instrumentos utilizados com o propósito de alcançar os objetivos da pesquisa foram a Observação, o Diário de Aprendizagem, Relatórios das Aulas de Campo e Comentários de Textos. Para a análise dos dados foram utilizados os cinco momentos previstos na própria PHC, teoria pedagógica de Dermeval Saviani, divulgada no Brasil nos anos iniciais da década de 1980 e “traduzida” didaticamente por João Luiz Gasparin, em 2002. A análise dos dados demonstra que a PHC foi um referencial metodológico que conseguiu articular de forma satisfatória o tema abordado / The ambient crisis that the planet faces has been reason of great concern for many countries. In the current civilization model it predominates wastefulness and the wild consumption. Of this form, the Environmental Education, in the partnerambient perspective starts to be an instrument of awareness in the intention to form citizens compromised to the change of values, attitudes and behaviors. One of the many ambient problems is the question of the water pollution. To understand the pollution of waters is of basic importance, since the preservation of its quality consists of preserving the proper life. Therefore, to leave of these questionings one searched, in this research, to work new a proposal for the pedagogical work: the Description-Critical Pedagogy (PHC); in order to answer the questions: Is possible to work in classroom the subject of the pollution of waters having as reference the Description-Critical Pedagogy as education methodology? Which the results of its application? To answer to these and other questions consisting in the way of the inquiry, one worked, during a period of learning semester, in the lessons of disciplines Biology, in a group of the Third Series of Average Education of a State Public School of the City of Bauru - SP. The instruments used in order to reach the objectives of the research had been the Comment, the Daily one of Learning, Reports of the Lessons of Field and Commentaries of Texts. For the analysis of the data the five moments foreseen in the proper PHC had been used, Dermeval Saviani’s pedagogical theory, divulged in Brazil in the initial years of the decade of 1980 and translated for João Luiz Gasparin in 2002. The analysis of the data demonstrates that the PHC was a method reference that obtained to articulate of satisfactory form the boarded subject
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